/Engine/Plugins/Interchange/Runtime/Source/FactoryNodes/Public/InterchangeTexture2DFactoryNode.h
Set the source blocks Using this will suggest the pipeline to consider this texture as UDIM and it can chose to pass or not these block to the texture factory node.
void SetSourceBlocks ( [TMap](API\Runtime\Core\Containers\TMap)< int32, [FString](API\Runtime\Core\Containers\FString) > && InSourceBlocks )